This invention relates generally to fluid displacement devices such as pumps, compressors, fluid motors and internal combustion engines.
Fluid displacing devices having pressure cavities volumetrically varied by piston rotors within spherical chambers are already known, as disclosed for example in U.S. Pat. Nos. 3,973,469; 4,021,158; 4,036,566 and 4,371,320. According to such prior patented devices, the pressure cavities are volumetrically varied by relative rotor rotation about an axis extending through the geometric center of the spherical chamber. According to some of such patents, the piston rotor is rotated relative to a stationary chamber partition. According to other of such patents, two piston rotors are rotated relative to each other about angularly related drive shafts. In the case of the device disclosed in U.S. Pat. No. 4,021,158 to Bajulaz for example, gearing disposed eternally of the chamber drivingly interconnects the rotor drive shafts. The piston rotors are otherwise independent of each other.
For various reasons, the aforementioned types of spherical chamber, fluid piston displacing devices have not enjoyed any significant degree of commercial success. It is therefore an important object of the present invention to provide a spherical chamber type of fluid displacing device which operates in a somewhat different manner than those heretofore known to thereby avoid the problems and drawbacks associated therewith and provide greater efficiency and operational reliability.